Here are 1 Bible verses about the key is within you, curated from both the Old and New Testaments of the Holy Bible, King James Version, arranged from most to least relevant.
Matthew 16:19 KJV
19 And I will give unto thee the keys of the kingdom of heaven: and whatsoever thou shalt bind on earth shall be bound in heaven: and whatsoever thou shalt loose on earth shall be loosed in heaven.